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The F-35 thread, Mk II

"2. They needed to deliver a decent sortie count, which meant a decent number of aircraft, which meant they had to be of a certain size, which meant that CTOL configuration became an option"

Interesting - the RAND study "Future Aircraft Carrier Options" back in 2017 has some interesting illustrations of how the perceived threat drives the response which drives the sortie rate which drives Carrier size. This was a major factor in the design of the "Fords"

"Of particular note is the fact that a major impetus for development of a carrier capable of supporting a high SGR (Sortie Generation Rate) was the Navy’s experience in Desert Storm, in which distances were short and the target environment rich. In such a context, high SGR would enable the faster delivery of ordnance and possibly a shortening of the campaign.

Even in the current environment, there are operational scenarios in which high SGR would be highly desirable, with defense against a swarm of small boats being one notable example. There is a large number of targets; the major detection sensor is radar and visual; the ability to use standoff munitions is limited. DCA in an environment in which rapid expenditure of air–air munitions is expected might be another.

In recent experience, however, there has been little need for large numbers of short sorties and a larger emphasis on longer-range sorties in which such features as ability to tank, ability to provide organic EA, and ability to provide long-range battle-space awareness are particularly important. Having the ability to rapidly generate sorties is not a detractor, but it has been less important than other features, and, in either case, the ability of current platforms to provide this support has been more than sufficient."

From memory, the six US CVBG on Desert Storm spent a lot of their time in the Red Sea or off Oman, which was hardly a "short trip". Only Midway (?) ended up in the Persian Gulf, adjacent to KTO. The more "recent experience" would appear to refer to OEF where a CVBG sits in the IO and provides ATO lines over Afghanistan - not exactly an exemplar.

The UK requirement was set against a number of scenarios developed in the mid-90s and the SGR derived from them. From memory they didn't include a large amount of CAS (except for one specific scenario), nor were FIAC a particular driver. They did include some significant warfighting phases and remain (generically) relevant.

The point about larger decks is that up to a certain point you're driven by safe parking requirement, which is largely about package size. Beyond which you get to a slightly bigger deck that enables reduced manning for a fixed SGR or a better SGR for a given deck manning setup, because you're not constantly re-spotting for the next launch / recovery serial - it's a marginal effect. The UK teams all went to visit Navy Lakehurst and interacted with the guys doing what became the Ford flightdeck design to examine operating drivers.

In case you're not aware how it works, the funding comes from the EAC (as was, now IAC last time I was involved) and is discussed in classified session, where the detail of the OA and economics is outlined (or more precisely, the plethora of studies that support the OR dossier, now IGBC is summarised). Prior to endorsing the requirement (itself a joint process under DCDS(EC)) and approving funding. For the avoidance of doubt, the EAC/IAC is a joint body, not something the Navy, Army or Air Force just pitch up at and ask for some money cos they feel like it.

The HCDC is an unclassified forum at which various pollies get to air their various hobby horses. Detail is not something they do - hence the level of brief from the witnesses. By the way, the "they" you refer to (assuming you mean Blackham) is the joint DCDS(EC) post, so many thanks for pointing out it was a joint endorsement......

At all stages from the endorsement of the original ST(S) in 1997, inclusion in SDR98 and onwards, it was clear that carriers were required and that they needed to be carriers from the off, not just a helicopter carrier with some make do and mends like their predecessors. It's just that some have always struggled to understand that relatively simple point. Not least because they equate size with cost, which is often far from the case. The real money is spent in a very different place from the surface fleet and carriers.

Been following the Green Demons since 1971, when I reported to fly one of their planes at The Beach. Outstanding unit.

Flew one to Korat in October 1972 for Linebacker II, and had the oppo to fly the same plane back to the states in December 1975 when the U.S. exited that stoopid war. Was my claim to fame, as my flight was last one of fighter bombers to leave the whole damned war!

The 356th FS should be of interest to all the RAF folks here that seem to own the forum. We flew Mustangs of 9th Air Force, but under operational control of 8th AF - the 354th Fighter Group, which had highest A2A kills of any wing ( don't pay attention to the 4th roosters).

One pilot wrote a well known book about their experience - "Big Friend, Little Friend".

The Pentagon will have to live with limits on F-35’s supersonic flights

WASHINGTON — An issue that risks damage to the F-35’s tail section if the aircraft needs to maintain supersonic speeds is not worth fixing and will instead be addressed by changing the operating parameters, the F-35 Joint Program Office told Defense News in a statement Friday.

The deficiency, first reported by Defense News in 2019, means that at extremely high altitudes, the U.S. Navy’s and Marine Corps’ versions of the F-35 jet can only fly at supersonic speeds for short bursts of time before there is a risk of structural damage and loss of stealth capability.

The problem may make it impossible for the Navy’s F-35C to conduct supersonic intercepts.

“This issue was closed on December 17, 2019 with no further actions and concurrence from the U.S. services,” the F-35 JPO statement read. “The [deficiency report] was closed under the category of ‘no plan to correct,’ which is used by the F-35 team when the operator value provided by a complete fix does not justify the estimated cost of that fix...........

Three other category 1 deficiencies have also been officially designated as “closed," meaning they have either been fixed or the performance of the aircraft is being accepted as is, the JPO reported.........

An issue created when the F-35A and F-35B blow a tire, which can result in a severed hydraulic line, will remain uncorrected, the JPO statement said, but it has not come up again since the program switched tires.

“The DR [deficiency report] was closed under the category of ‘no plan to correct’ based on the fact that the landing gear system design meets all F-35 safety standards,” the statement read. “Issues related to premature bursting of tires were resolved by tire design changes during early F-35 development and no instances of dual hydraulic system loss caused by a tire burst have ever been observed on an F-35.”.......

Well, ORAC. big deal. Not sure about your experience making intercepts at 1.3M or above, and ditto for combat experience. Profile is lacking on those details. Unlike the Raptor spec that needed "supercruise", the Stubbie needed to have some supersonic capability, but not its primary A2A requirement. I, too, was surprised about some of the complaints

Quote:

the F-35 jet can only fly at supersonic speeds for short bursts of time before there is a risk of structural damage and loss of stealth capability, a problem that may make it impossible for the Navy’s F-35C to conduct supersonic intercepts.

That was in 2011!

Quote:

Both deficiencies were first observed in late 2011 following flutter tests where the F-35B and F-35C both flew at speeds of Mach 1.3 and Mach 1.4.

Think newer RAM and such might be used now? And I have not seen one reference to "structural" damage.

Unlike the early Hornets, where areo forces on the twin tails caused actual damage. McAir had closed the slots on the LEX of the YF-17, and that resulted in increased buffet and forces on the vertical tails.

There are many who wish to keep the old and faithful birds around that they like or personally have not flown a combat mission in the last 30 years, or even ever.... I think of McCain and his support of the Warthog. Now we have the Hornet mafia. USAF loves its Vipers, but this new jet has all they want and more - ask a few.

The Stubbie can do its missions very well, even beyond what was expected. More misisons than the Raptor or the Rafale or the Tiffie or the brand "x" from some other places. It was never intended to zoom out at the speed of stink and shoot down some enema planes way up in the stratosphere.

I would take the testimomny of those that have flown it and also have flown the Gen 4 planes. Combat experience would be nice, but we haven't had the "luxury" that some of us had back in the 70's, 80's and 90's. Those of us back then had the chance to fly "cold war" iron, then the early computer jets, and then stealth machines.

The F-35 is doing well, considering its complexity ( something I balked about, and that still concerns me), but it looks to be a game changer in the actual arena.

Bugging out these days doesn't mean you have to be at 1.5 M for a minute. Even back in my day we only needed to gain 200 or 300 knots in 30 seconds and the bad guy could watch our 36 inch tail pipe turning into a dot. That's assuming his Atoll or Aphid or Archer wasn't chasing us. So the biggie is to be able to rapidly accelerate while staying outta the other guy's launch envelope. Tuff these days with the off-boresight capabilities, but still a great capability to have. Besides, the mach numbers in the spec are usually not related to time to get there from "x" mach. Our Vipers could reach 2.0M, but took us well over a minute from 0.6M or so, more if still loaded with missiles. OTOH, we got to 1.1M or thereabouts within 15 or 20 seconds in a shallow descent.

Speed for height trades seem to be something Frank Luke and Richenbacher and that Hun ace learned a hundred years ago. Guess some things remain true. Heh heh. Supersonic? Well, I'd take 0.85M and be able to climb at a 30 deg angle without losing energy than a very short high pitch and then the slow speed recovery.

The tail chase is passe nowadays, and it was literally that way when I flew interceptors in the 60's. I only wound up in a tail chase when the controller rolled me out cold. Our NORAD standard stern attack was based on 50 knots overtake and a coupla miles at 6. The folks here that were not controllers need to realize that it takes 6 minutes to gain a mile on that sucker when 10 knots faster. So around a minute at 50 knots for each mile. Up at 0.9M you need burner to get any overtake on a co-speed tgt, so supersonic is a requirement. I learned the hard way chasing a B-58 one night. So the secret is not to wind up in a tail chase. On most A2A intercepts now, we see HO or beam geometry, so total speed not a biggie. Nice to have, but I prefer my extra 1,000 pounds of gas.

Anyway, the supersonic stuff seems to appeal to a few that have little recent operational or combat experience in the A2A arena. The acceleration for bugging out or for a maneuver to gain an advantage or survive is more important than 1.3M that requires 30 or 40 seconds full blower.

Lockheed Martin Comments on Defense News Reporting

The F-35B and C deliver on all performance requirements. The potential for tailboom or horizontal tail damage during prolonged supersonic speeds was found in the highest extremes of flight testing conditions that are unlikely replicated in operational scenarios. In fact, there have been no cases of this issue occurring in the operational fleet. Additionally, this is not identified as a safety of flight concern.

We implemented a change to the coatings on the horizontal tails and tail boom beginning in Lot 8 that increases durability and resolves this concern. This update allows the F-35B and C to deliver on all performance requirements with no tail boom or horizontal tail damage concerns.

Maybe the RAF folks could visit the F-35 forums over at F-16.net, and see some of the discussion re: required operational capability requirements, test results, opinions and such.

The test profiles for the Stubbie were about as benign as with most planes since the P-36. Wind up turns, climb steps, acceleration profiles, etc. And they still do things like one gee st and level at max power to get the time to accelerate from "x" to "y". If this jet can go from 0.8 to 1.2 in 8 seconds while st and level, then it beats about every jet since the early F-104's in the 50's, and the F-101B' a few years later. I only flew three jets that were true supersonic designs, and even the Viper could not go thru the mach from 0.8M in a few seconds unless going down hill. The VooDoo back in its day was actually better than the Viper, and we could bunt over to a half a gee or so at 20K on a max burner climb and go thru the mach while still climbing thru 25K , then climb at 1.3M or so to over 50K. The Zipper folks have as good or better war stories, as do the RAF Lightning folks.

ORAC's observation about fuel is the biggie. Ask any Eagle, Viper, Hornet, Tiffie, Rafale, 'nado pilot how many seconds they flew supersonic in an engagement once past the merge. Getting to the fight or intercept is a different aspect of the scenario.

@ Once, my "supersonic to the intercept" thot was pre-Slammer. The Slammer gave us the capability to shoot way out there with little or no giant white plume like the Sparrow. We didn't need the speed. The intercept geometry might still make a supercruise capablility a player, but most engagements since the early days of VietNam were not the stereotypical stern conversions that ORAC is very familiar with. Read some of the Combat Tree stuff and the 1972 engagements using Teaball and such.

The modern A2A scenarios favor gaining and maintaining energy for the areodynamics, super situational awareness ( like the Stubbie has) and missiles that can be launched and hit from parameters we could not dream of back in the day.

So the supersonic stuff is passe except for the RAM that might need to be re-applied to keep the RCS down to the level of a house wren.